Oil circulatory system employed in fuel injection pumps



Feb. l9, 1946 E,-HOUSER OIL CIRCULATORY SYSTEM EMPLOYED IN FUEL INJECTION ?UMPS Filed Spt. 11, 1942 2 Sheieks-Sheet l INVENTOR JESSE E-HOU-SER,

ATTORNEYS Feb; 19, 1946. J. E. HOUSER 2,395,330

OIL CIRCULATORY SYSTEM EMPLOYED IN FUEL INJECTION PUMPS I Filed Sept. 11, 1942 2 sheets-sheet 2- INVENTOR JESSE E. HOUSER,

ATTORNEY5 Patented Feb. 19, 1946 OIL CIRCULATORY SYSTEM EMPLOYED IN FUEL INJECTION PUMPS Jesse E. Houser, Dayton, Ohio, assignor to The Dayton Liquid Meter 00., Dayton, Ohio, a corporation of Ohio Application September 11, 1942, Serial No. 457,965

12 Claims.

The present invention relates to improvements in a method of and apparatus for injecting fuel into automotive engines;

In the case of high power, high speed automotive engines, more particularly those employed in connection with aircraft, there has arisen a marked necessity for devices which will inject fuel of all kinds directly into the respective cylinders of the engine, or into the intake manifold, with a high degree of accuracy of measurement. These injectors are usually employed as a substitute for the ordinary forms of carburetion, leaving to the injection pump the Very important function of accurately measuring the amount of fuel in the successive charges.

For this purpose it has been customary to employ a plunger attachedto a fuel suction line which reciproeates in a cylinder carrying a spray nozzle. This nozzle is sometimes introduced directly into the respective cylinders of the engine, and in other cases it is inserted in the intake manifold. In order to lubricate this fast moving plunger, passageways which extend from the interior of the cylinder, and a source of lubricating oil are employed. However, it has been found that this ofl which thus accumulates on the periphery of the plunger tends to dilute the fuel, particularly as the engine runs hot, thinning the oil. Moreover, the sediment, and other foreign material which may be of an abrasive character and contained in the fuel, tends to find it's Way into the lubricating system, thus causing excessive wear on the reciprocating parts.

In the Houser et al. Patent No. 2,301,407, granted Nov. 10, 1942, there is disclosed apparatus and method by which these drawbacks are overcome. In general, this method employs the step of confining the fuel to be injected in a compartment having a flexible wall and causing flexure' of the wall by pressure fluid, preferably oil,

in timed relation with the operating cycle of the engine.

This. method may be carried out'according' to the invention set forth in my patent by a fuel injector pump which includes a flexible member separating from each. other two compartments, the first of which is adapted to receive fuel to be injectediinto an automotive engine, while the second compartment is adapted to receive fluid, preferably oil, and comprises means for subjecting the: fluid to pressure in timed relation with the operating cycle of the engine to cause the flexible member to move in accordance with the igniting cycle.

In this way the fuel passing through the injector pump is maintained entirely separate from the lubricating system so as to eliminate any transfer of oil into the fuel system, and also to prevent foreign matter from moving between the fuel system and the lubricating system; It has been found that when the oil content of the plunger compartment forms part ofa closed circulatory system, certain gases such as vapor or air bubbles are driven out of solution from the oil due to surge effects and may remain out of solution for considerable periods of time. These noncondensables serve to reduce the accuracy with which the plunger translates'its movement into changes of pressure at the diaphragm and therefore into changes of volume of the injected fuel.

The non-condensables are eliminated in accordance with the invention disclosed in said pat-- cut by means of a chamois separator which permits the oil in which the condensables are dissolved to pass but retains the free gas or other non-condensables. Apparatus of this character has operated satisfactorily in case the improved device is used in connection with vehicles which move substantially in a single plane, for example, automobiles passing along the highway. Satisfactory results are also obtained in the case of airplanes and particularlyif the plane is not banked too steeply or otherwise where the changes of position are not too abrupt. Under these circumstances, the level of the fluid, oil, etc. within the separator remains substantially stationary. I

In accordance with the present invention, improvements are introduced into the oil circulatory system by which the necessity for such a separator is eliminated in order to adapt the apparatus as va whole to vehicles which move in any plane or combination of planes orwhich shift from one plane to another at asteep angle. In general, this improvement consists in forcing the gas bubbles or other non-condensables immediately back into solution as the oil is being circulated so that there are no non-condensab'les in a permanently free state. The oil is placed under pressure of a predetermined and variable amount in such a manner that the gas bubbles or other noncondensables are caused to be instantly and completely re-absorbed within the oil.

The primary object of the present invention is to provide a practical device for maintaining the oil free of non-condensables or rather to prevent the gas bubbles which are thrown out of solution from returning to the plunger compartment through the closed circulatory system'-- in a free or dis-associated state and which might reduce the accuracy with which the improved injector meters the fuel. The general object of the invention is to provide an accurate measuring device for controlling the injection of fuel into automotive engines, and in which the force of injection is obtained through hydraulic pressure; and in which the non-condensables or other foreign material thrown out of the oil solution are caused immediately to be forced back into solution.

Other objects and features will be apparent as the specification is perused in connection with the accompanying drawings.

In the drawings: 7

Figure 1 represents a diagrammatic view of a typical engine provided with the improved inje-ctor'pump for controlling the flow of fuel to the respective cylinders.

Figure 2 is a sectional view, partly in elevation of the improved pump together with an accessory by which dripping at the injection nozzle is prevented.

Figure 3 is a fragmentary sectional view of the improved injector pump showing the position of the various parts of the pump under full throttle conditions.

Figure 4 is a longitudinal sectional view, partly in elevation, of the improved compensator which is inserted in the circulatory system and serves to force the non-condensables back into solution. This figure also shows the condition of the .oil, particularly the upward movement of the air or gas bubbles travelling through the oil under full throttle condition at the engine.

Figure 5 is a view somewhat similar to Figure 3 but shows the relative position of the parts of the injector under low throttle condition.

Figure 6 is a view similar to Figure 4 except that it shows the conditions within the oil pertaining to the low throttle adjustment illustrated in Figure 5.

Figure 7 is a sectional view of a modified form of compensator.

Referring more particularly to Figure 1, the reference character I generally designates a typical form of automotive engine as specifically six cylinders, indicated by the six spark plugs 2.

The engine block is shown at 3 and the bed at 4. Only the left hand cylinder has been shown in detail and this cylinder contains a piston 5. The bed of the engine is provided with a flange 6, and on this flange rests as many injector .pumps of the improved type as there are cylinders, these pumps being preferably secured to the engine and positioned directly below the respective cylinders.

The parts of the improved injector pump are contained within a casing I, which may be of a general cylindrical form, and from the upper portion of each casing there is a fuel intake line 8 which connects through a common pipe 9 to a fuel tank (not shown). There are fuel discharge pipes it taken from the upper end of the casing and terminating at each cylinder just above the uppermost position of the piston 5. There is also a set of pipes secured to the side of each casing 1, the upper pipe serving as an oil inlet pipe and the lower pipe l2 serving as an oil outlet pipe, the circuit being completed through an improved oil compensator l3, the construction of which is shown to the extreme left in Figure 1. The details of the improved injector pump are illustrated in Figure 2.

The casing 1 is actually constituted of two,

members, joined together by screws M. The upr .the annular groove 44, there is,a similar groove.

per casing I6 is provided with multi-shouldered portions l1, l8 the latter terminating in a screw threaded member l9 to which the pipe l0 is'secured by any suitable form of coupling 20. There is a cylindrical opening 2| passing down through the casing l6 and in line with the opening in the discharge pipe l0. I

The opening 2| has the same diameter down as far as the shoulder 22, and the opening emerges into another opening of smaller diameter, indicated at 23. At the lower part of the opening 2| and'resting on the shoulder 22 there is a hollow assembled member 24 (Figure 2) which has a transverse portion (not shown) containing two diagonally directed openings (not shown) A pin (not shown) projects downwardly from the transverse portion or web (not shown), this pin being in line with a ball 28 which in cooperation with the opening 29 at the bottom of the thimble constitutes a check valve. It will be apparent that the pin referred to hereinbefore merely serves to limit the upward movement of the ball when pressure is applied to the fuel passing through the thimble 24. The upper casing I6 is also provided with atransversely extending opening 30, which contains a sleeve 3| having a centrally aligned aperture 32. The ball 33, forming part of a second check valve, is urged by the spring 34 against the left hand end of the opening 32. There is a projection at 35 extending to the right (Figure 2) of the easing Hi, this projection being threaded to receive a coupling 36 for securing the fuel inlet pipe 8 to the casing in line with the opening 30.

The casing H5 is. provided at its lower end with a countersunk conically shaped opening 31, this opening being adapted to receive a diaphragm 38, preferably of a steel' composition which resists corrosion by all the known types of fuel. This diaphragm may have any desired figure but performs its function described hereinafter particularly well when the thickness is left at /1000 of an inch. The diaphragm is seated between an annular rim portion formed on the .casing H5 at the upper surface of a lower casing 39 of the fuel injector pump which together which receives the plug 52, there is a radially extending opening 54, the purposes of which will be explained'hereinaf-ter. The upper end of the plug 52 terminates in a small diameter portion 55 which receives a compression spring 56 for .urging theball 5'! against the underside of the opening 5|.

changed. There is an annular opening 58 cuppedinto the upper surface of the sleeve 58. For rotating the sleeve, there is provided'a gear 59 which is journalled at 6B in a projection 6| extending from the casing 39. The gearis keyed to a shaft 62 and the latter is adapted to be rotatecl by means of a hand operated throttle lever 53. The teeth of the gear 59 mesh with teeth formed at the lower end of the sleeve 58. Consequently, by rotating the lever 63 the sleeve-58 is rotated at a corresponding rate and is moved upwardly or downwardly, depending on the di rection in which the lever 63 is moved.

There is a plate 64 screwed to the underside of the projection member BI and the casing 39, this plate having depending therefrom a cylinder 65 which terminates in a flanged portion 66. The latter is secured to a portion 6'! of the engine frame directly above a cam shaft 68. The latter may be any one of the cam shafts of the engine and have secured thereto a cam 69. The cylinder 65 is hollow and has a shouldered compartment in which is rigidly secured a sleeve Hi. In the sleeve, there is a solid cylindrical member H adapted to reciprocate and carrying at its lower end a shaft 12 on whichis mounted a cam follower 13 substantially of circular configuration. The upper portion of the cylinder H is countersunk to receive the lower or enlarged portion of the plunger 43. The latter is secured to the cylinder H by a nut 14 which fits about the upper side of the enlarged portion. There is a compression spring contained within the annular space between with sleeve and the interior of the cylinder 65, the lower end of the, spring surrounding the sleeve-like spring holder 15 which is secured to the sleeve 10. It is apparent that as the shaft 68 is rotated, the cam 69 will cause the follower '13 to move upwardly and downwardly and thereby causing reciprocations of the cylinder H and the plunger 43.

It was pointed out in connection with Figure 1 that the pressure fluid lines H and I2 communicate with an oil volume or pressure compensator I3. This compensator will now be described.

The element shown to the extreme left of Figure 1. represents onlyone of themany forms that the compensator may take. As illustrated, the compensator comprises a cupped shaped casing 16 preferably of metal with a cover 11 bolted thereto as indicated at 18. The cover 11 is provided with a needle release valve 19 to one sideof its center and there. is a large opening 80 in the center. A tubular member 8| is positioned within the opening 88 and the upper end of this member is provided with threads indicated at 82. A relatively thick metal cap 83 is threaded on its interior to engage the threads of the member 8!.

The cap is provided with a downwardly'extending centrally disposed stub 84 which bears against the upper end of a compression spring 85'. The other or lower end of the spring is seated on a cap 86 which is secured to the end of a Sylphon bellows 81:. The. fixed end or the bellows is rigid- 1y seriured to the lower end of the tubular member8 1 l It is apparent that as the cap 83 is rotated the stub 84 forces the lower end of the spring 85 downwardly which in turn moves the lower side of the bellows. Inasmuch as the upperside of the bellows is fixed, the effect of rotating the cap 83 is to increase the length of the bellows and its volume. This in turn causes an increase of the pressure introduced into the surrounding fluid. Thus the cap 83 serves to place the oil or other fluid contained within the casing 76 under any predetermined andadjustable pressure.

The bottom of the casing 16 is providedwith a central opening and an opening at the side into which inlet and outlet fixtures 88, 89 respectively may be fitted in order to receive the inlet and outlet pipes 12 and H. A cylindrical barrier may. also be provided for purposes which will be explained presently, this barrier being secured to the bottom of the casing 16 and positioned soas to surround the inlet fixture 88. It will be understood that all of the joints about the casing including the inlet and outlet fixtures 88, 89 and the bolted edge '18 aremade strictly fluid tight so that the casing 16 may be filled completely with oil or other pressure fluid for operating the injector pump shown in Figure 2. The needle valve 19 may if desired be used as a convenient way for introducing the oil into the casing although the main purpose of this valve is to relieve any excessive pressure that might develop within the casing 16 over a long period of time. Assuming that the casing 16 has been completely filled with oil, and the cap 83 given its proper adjustment, the compensator will serve to force the air and gas bubbles which had thrown out of solution at the position of the pump back into solution as the fluid makes its circulatory passage through the pipes II and I2. A detailed description of the operation of the compensator will be given in connection with the operation of the injector pump shown in Figure 2.

Operation of the fuel injection pump and its compensator accessory Referring to Figure 2 which. represents the starting position of the various parts of the pump, let us assume that the fuel has been drawn in from the. pipe 8 through the opening 30, 32 past the check valve 33 and into the space directly above the diaphragm 38. The cam 69 is in its lowermost position causing the plunger 43 tobe also withdrawn to its lowest position. Under these circumstances a partial vacuum will be formed within the bore 42 directly above the plunger, causing oil to be withdrawn from the outer annular space of the compensator l3 through the pipe I I, openings 41, 46 and 45. Thus the bore 42 is completely filled with oil or other relatively incompressible pressure fluid.

As the cam 69 rotates, the plunger 43 is caused to be elevated closing off the opening 4-5 and finally placing the trapped oil under pressure. The increased pressure produced by the plunger on the trapped oil serves to flex the diaphragm 38 causing a reduction in the volume of the space directly above the diaphragm. This, in turn, produces a large increase in pressure on the fuel trapped above the diaphragm, causing the ball 33 to be firmly seated against the sleeve 3|, thereby closing off the inlet passage 32 and also forcing the ball 28. in the discharge passageway to be moved. away from the opening 29. Fuel under pressure. is therefore paused to pass upwardly through the passageway 23, 29, through the di-" agonal passageways into the respective pipes II) which lead to the cylinders of the engine. From the pipe In, the fuel is caused to pass under extremely high pressure and to be ejected as a spray of circular configuration into the cylinder of the engine.

It will be understood that there are as many earns 69 and fuel injection pumps as there are cylinders, as indicated in Figure 1, and the cams are so positioned with respect to the cam shaft 68 (Figure 2) as to cause the circular spray to leave the respective nozzles in proper timed relation, depending on thefiring' order of the engine cylinders. As the plunger 43 (Figure 2) continues to rise, due to the actuation of the cam 69, fuel is elected at the nozzle until the fluid pressure within the plunger bore 42 is released. This pressure releasing function is obtained by the upward movement of the radial opening 54, which as soon as it uncovers the annular opening 58' permits the oil under pressure in the bore 42 to pass through the longitudinal opening 5| and to unseat the check valve 51 against the spring 56, thereby allowing the oil to pass through the radial opening 54 in the plunger and through the annular opening 58. This annular opening communicates with the openings 48, 49 and 58, thus permitting the oil to move through the pipe l2 into the inlet fixture 88 where the oil is subjected to the pressure exerted and controlled by the thickness of the Sylphon bellows 81 which in turn is controlled by the cap 83.

The compensatorwill serve in the manner described hereinafter to force all non-condensables such as air and gas bubbles back into solution and thus to assure the maintenance of a 100%, noncompressible iluid introduced into the bore 42. The upward travel of the plunger 43 is therefore translated directly and accurately into changes of pressure in the oil, which in turn, causes accurate flexing of the diaphragm 38 and an accurate measurement of the fuel expelled at the nozzle. The smallest amount of a compressible medium such as air or vapor in the oil, and particularly when this air or vapor appears as bubbles disassociated from the body of the oil, i. e. out of solution, may cause, for a given travel of the plunger, a disproportionate movement of flexing of the diaphragm, thus introducing errors in the amount of fuel ejected at the nozzle. These air or vapor bubbles may be driven out of the oil solution by extreme agitation produced in the oil when the pressure in the latter is released by permitting oil to flow through the opening 5|, past the check-valve 51 and through the passageway 54, into the compensator I3.

It is apparent that the less the throttling effect produced by the upward movement of the sleeve 58, the less will be the tendency for the air or vapor bubbles to be driven out of the oil solution.

This is-because the agitation produced in the oil is less. Consequently, there is a greater tendency for the air or vapor bubbles to become disassociated from the oil solution when the ejector is so adjusted that the engine runs on only partial throttle. This greater tendency for the air and gas bubbles to become disassociated from the oil as the throttling effect at the injector pump becomes greater is significantly illustrated by a comparison of Figures 4 and 6. These figures have been placed opposite their respective injector setting in order to show the relative positions of the sleeve 58 for the difierentthrottle conditions. Thus the condition shown in Figures 3 and 4 on the one hand, and in Figures 5 and 6 onthe other hand represent full throttle and partial throttle respectively. In each of Figures 4' and 6 there is a plume arising from the inlet fixture 88, this plume taking the general form of an inverted cone the apex of which is contained within the fixture 88. This plume is made up of an extremely large number of air or gasbubbles of varying size, generally quite small which tend to difiuse upwardly and outwardly away from the fixture 88. The height and size of this.

plumegives an indication of the tendency of the air and gas bubbles to leave the oil solution. Under full throttle condition (Figure 4) this tendency is much less than under partial throttle (Figure 6). It is apparent that the function of the cylindrical barrier 98 is to prevent any stray gas or vapor bubbles from traveling directly between the inlet fixture 88 and the outlet fixture In accordance with the main feature of my invention, the plume 9| is completely eliminated or at least reduced to a minimum by applying pressure to the oil through the use of Sylphon bellows 81. It has been pointed out hereinbefore that as the cap 83 (Figure 1) is turned, the thickness of the bellows may be made greater or less depending on the amount of pressure desired to be introduced into the oil. In general the adjustment of the cap 83 is so determined that there is little or no plume, even when the engine is being operated under partial throttle conditions and under these conditions there is even less tendency for a plume to be present when the engine is being operated at full throttle.

This adjustment can be determined either visually as when the casing 16 is made of a transparent material or contains a window. through which the plume can be observed, or if desired,

0 the proper pressure introduced by the bellows may be determined experimentally by the manufacturer and the cap permanently left in an average position. An index (not shown) may be provided on the cap and the manufacturer may supply a chart with recommended adjustments for is automatically and instantly effective to force the molecules back into solution as the oil reaches the compensator. Viewed from another aspect, the efiect of the'pressure is to assure that the oil in the compensator contains all of the air or vapor that it can possibly absorb at the given temperature and pressure so that the oil always acts as an incompressible medium. It should also be noted that inasmuch as the casing 16 is completely filled with oil, the compensator may be usedin any position since there can be no swishing of the liquid in the oil system and the fluid system as a whole lends itself to use connection with a vehicle moving in any plane, direction, or combination of planes or directions. It is also apparent that the flexible character of the compensator takes care of any air or gas leakage anywherethroughout the oil circulatory system including theiniector pump, thus assurasoaaso a relatively solidtand incompressible column of. oil the system.

Figure I shows a modified form. of compensator which lends itself. all, the more, readily toward preventing any movement of the disassociated gas or vapor bubbles. from the inlet. fixture 88, to the outlet fixture: 89 regardless of the instantaneous position that the compensator maytake. As is the; casein Figure l thev unit shown in Figure 7 takes the form of a two-part casing. of metal or other suitable material bolted together as indicated at 78. The top side.- of the. Sylphon bellows 81 is. secured directly to 'thee left hand portion of the casing 16, and otherwise, the adjustment mechanism is exactly the same; as, has been shown and described in connection with Figure 1. There is a pair. of baflles 92 extending across the main portion of. the casing- 16, these baffles being provided with a central opening indicated at .93... An intermediate baffle 94' is; positioned between the bafilest92, this intermediate baflle being. mounted in. position. on a stud 95 whichmay be conveniently secured to the bottom side of the casing. The inlet fixture is. indicated at: 88 and. the outlet fixture is. illustrated at 88. as in the case of Figure 1. It is apparent thatI should any plume of disassociated' gas or vapor bubbles form. near the inlet fixture 88, assuming that the cap 83 has not been properly adjusted, these gas or vapor molecules could not find. their way to the outlet fixture 89 due to the extremely tortuous path provided between the various areas. This path is so long that. the gas or vapor bubbles would be bound to enterthe. liquid and thus be absorbed thereby before they could reach. the. outlet fixture 89. It will be. understood that if the bellows. 81 were properly adjusted, all gas and vapor bubbles will idly. In sucha case, the direction in. which the disassociated gas. and vapor molecules are caused to. move by the action. of gravity, should such disassociated molecules appear, would constantly change so that. a baffle. effect should be provided in each and every direction. This is. effectively accomplished in the device shown in Figure 7..

WhileIi prefcrto use a. Sylphon bellows. for the pressure introducing element, other devices may be used to advantage such as a; flexible wall or metal diaphragm which may be flexed by operating the cam 83. A spring biased movable wall may also be used for this purpflse, in fact, any convenient device for applying pressure to the liquid and controllable at: the. cap 83.. A rubber cylinder or ball. filled with air under pressure and completely submerged in the oil could be used but in such a case. there would be no adjustment possible at the cap 83., However, the cylinder or ball would serve continuously and automatically to increase the pressure applied to the oil until the pressure inside and outside of the submerged enclosure are the same, thus in effect, placing the oil or other pressure fluid under the proper amount of pressure to force the non-condensables back into solution.

It will be understood that I desire to comprebend within my invention such modifications as come within the scope of the claimsand the invention.

Having thus fully described my invention, what I claim. as new and desire. to secure by Letters Patent, is:

1.. In. combination, an injector pump which in.- cludes a plurality of compartments. separated by a flexible wall one of. said compartments being adapted to contain fuel and the. other of said. compartments being adapted to contain. pressure fluid, an, injection chamber including a fluid circulatory system for causing the pressure fluid to flex said wall and thereby to place the fuel under pressure, means positioned in said circulatory system but positioned remote from said pump for placing, the

fluid in the system under. pressure in order to force disassociated non-condensables in said fluid back into solution during the flexing of said wall. 2.. In combination, an injector pump which includes. a plurality of compartments. separated by a. flexible wall, one. of said compartments. being adapted to contain fuel and the other of said compartments being adapted tocontain. pressure fluid,

an injection chamber including a fluid circulatory system but positioned remote from said. pump for causing the pressure fluid to flex said wall and thereby to place the fuel under pressure, means positioned in said circulatory system for, placing the fluid in the system under pressure; in order to force disassociatednon-condensables in said fluid back into solution during the flexing of saidwall, said means comprising a casing which receives at least a portion of the pressure fluid and a volumechanging device in said casing for subjecting the fluid to a predetermined pressure.

3. In combination, an injector pump which includes a plurality of compartments separated by a flexible wall, one of said compartmentsbeing adapted to contain fuel and the other of said com.. partments being adapted to contain pressure fluid, an injection chamber including a fluid circulatory system for causing the pressure fluid to flex said wall and thereby to placev the fuel under pressure, means positioned in said circulatory system for placing the fluid in the system under pressure in order to force non-condensables driven out of solution in said pressure fluid during the flexing of said wall back into solution, said means comprising a casing which receives. at least a portion of the pressure fluid, and a volume-changing device in said casing for subjecting the fluid to a predetermined pressure, said device comprising a Sylphunbellows adjustable in size from theexterior of the casing.

4. In combination, an injector pump which includes a plurality of compartment separated by a flexible wall, one of said compartments being adapted to contain fuel and the other of said compartments being adapted to contain pressure fluid, an injection chamber for causing the pressure fluid to flex said wall and thereby to place. the fuel under pressure, and, means positioned remote from said pump for forcing non-condensables driven out of solution in said pressure fluid when the wall is flexed back into solution. l

5. In combination, an injector pump which includes a plurality of compartments separated by a flexible wall, one of said compartments being adapted to contain fuel and the other of said compartments being adapted to contain pressure fluid, an injection. chamber for causing the pressure fluid to. flex said wall and thereby to place the fuel under pressure, and means positioned remote from said pump for forcing non-condensables driven out of solution in said pressure fluid when the wall is flexed back into solution, said means including a device for applying a constant predetermined pressure to said pressure fluid.

fuel ejectedfrom the fuel-containing compartment represents an accurate and predetermined amount.

7. In an injector pump'which includes two compartments separated by a flexible wall, one f said compartments being adapted to contain a pressure fluid and the other compartment being adapted to contain a fuel, means for applying suflicient constant pressure to a segregated por-' 'tion of the pressure fluid to force non-condensables that had become dis-associated from the fluid back into solution whereby as the flexible wall is'flexed during operation of the pump, the

fuel ejected from the fuel-containing compartment represents an accurate and predetermined amount. 7

g 8. In combination, an injectorpump which includes'a plurality of compartments separated by a flexible Wall, one of said compartments being adapted to contain fuel and other of said compartments' being adapted to contain pressure fluid, an injection chamber for causing the pressure fluid to flex said wall and thereby to place "the fuel under pressure, means for forcing the non-condensables driven out of the fluid when the wall is flexed back into solution, said means com- "prising a casing through which the fluid is caused to flow, inlet and outlet fixtures in said casing, and a baftle between said fixtures, and means posi- :tioned within said casing for applying a predetermined pressure to said fluid suflicient to force the' non-condensable s back into solution during the flexing of said wall.

' 9 In combination, an injector pump which in- 1 cludesa plurality of compartmentsseparated by a flexible ,wall, one of said compartments being j'adapted' to contain fuel and the other of said compartments being adapted to contain pressure fluid, an injection chamber for causing the pressure fluid to flex said wall and thereby to place the fuel under pressure, means for forcing the non-condensables driven out of the fluid when the wall is flexed back into solution, said means comto flow, said casing having inlet and outlet fixturesfor the fluid and a device adjustable from the exterior of the casing for applying a predetermined pressure to the fluid, and means include a plurality of laterally extending baffies which form a tortuous path for preventing a direct movement ofv the fluid betweenthe inlet and outlet fixtures.

10. In combination, an injector pump which,

by a flexible wall, one of said compartments being adapted to contain fuel and the other of said compartments being adapted to contain pressure fluid, an injection chamber for causing the pressure fluid to flex said wall and thereby to place the fuel under pressure, means for forcing the non-condensables driven out of the fluid when the wall is flexed back into solution, said means including a casing through which the fluid is caused to pass, said casing having a centrally disposed inlet fixture, an outlet fixture positioned remote from the inlet fixture, and a device for producing pressure in the fluid mounted directly above the inlet fixture.

11. In combination, a fuel injector pump which includes a plurality of compartments separated by a flexible wall, one of said compartments being adapted to contain fuel and the other of said compartments being adapted to contain pressure fluid, an injection chamber-for causing the pressure fluid to flex said wall and thereby to 7 place the fuel under pressure, means for forcing the non-condensables driven out of the fluid when the wall is flexed back into solution, said means comprising a casing through which the fluid is caused to pass and an adjustable device within the casing for subjecting the fluid to a predetermined pressure, said device including a Sylphon one end of which is immovably secured to the casing and the other end is movable with respect thereto in order to change its volume and thereby change the pressure exerted on the fluid, a screwelement' projecting from one side of the casing in line with the Sylphon, a cap adapted to prising a casing through which the fluid is caused includes a plurality ,of compartments separated engage the threads of said screw, an opening in the casing in line with saidcap and Sylphon, and a spring interposed between the cap and the end of the Sylphon so as to apply pressure to the latter when the cap is turned on said screwelement. 12;'In combination, a fuel injector pump which includes a plurality of compartments separated by a flexible wall, one of said compartments being adapted to contain fuel and the other of said compartments being adapted to contain pressure fluid, an injection chamber for causing the pressure fluid to flex said wall and thereby to place the fuel under pressurameans for forcing the non-condensables driven out of the fluid cluding at least one baffle so arranged that any non-condensables which may tend to be thrown out of solution will be prevented from passing directly between the inlet and outlet fixtures reardless of the instantaneous position of the casing' in space.

JESSE E. I-lOUSER'. 

